1. The Field of the Invention
The present invention relates to a collapsible bulk storage containment system that has the rigid features of a fiber board box along with the flexibility or collapsibility and liquid integrity of a bulk bag.
2. The Prior Art
Previously manufactured bulk shipping containers have either used a bag approach or rigid container approach, both of which have their advantages and their disadvantages. The bag type containers are easily shipped and stored in an empty condition, but frequently they generally do not have sufficient rigidity, especially when filled with liquid or fluent material, to allow stacking of the filled containers. They also have presented problems in loading and particularly in unloading in that they easily shifted relative positions during transport making it substantially impossible to unload them with mechanical devices, such as fork lifts, without penetrating the bags. The rigid containers clearly have sufficiently rigid structure to allow stacking when filled or partially filled with liquid or fluent material, but they cannot be collapsed and thus take up a lot of room for transportation and storage when empty. Many of the known bag and rigid containers do not have any provision for compartmentalization of the storage region in order to provide for multiple materials to be loaded in the container in segregated fashion.
One recent attempt to overcome the above mentioned difficulties is found in U.S. Pat. No. 4,903,859. This patent discloses a container which is made from two layers of flexible material which form a pocket therebetween. At least two rigid members are inserted into these pockets to form opposing rigid side walls when the container is assembled. The top and bottom of the container are closed by excess material, there being no top and bottom members or portions as such. A somewhat similar approach is found in U.S. Pat. No. 3,896,991.